This invention relates to a double layer mug, particularly to one possible to enduring high temperature, provided with an intermediate hollow layer containing decorative matters visible from outside to arouse attention and desire of consumers.
A known conventional double layer mug of Taiwan Patent No. 84212234 publicized on Dec. 12, 1996 includes an outer layer 1, an inner layer 2, an anti-leak gasket 3, and a bottom 4 as main components, as shown in a copy of the patent.
The outer layer 1 is made of plastic, having a center hollow, and an annular recess 10 in an inner surface near an upper edge, and a grip 11 fixed on an outer surface for holding the mug.
The inner layer 2 is made of a metal, fitted in the outer layer 1, and having an annular groove in an upper end.
The anti-leak gasket 3 is fitted in the annular groove 20 of the inner layer 2.
The bottom 4 is located at the lower end of the outer layer 1, having a plurality of triangular chocks 40 laid on an upper surface for positioning the inner layer 2.
Further, a cool agent is poured in an intermediate layer formed between the outer layer 1 and the inner layer 2, prevented from flowing in the inner layer 2 by means of the anti-leak gasket 3. Thus this double layer mug has a cooling function.
However, though the inner layer is made of a metal heat-enduring, the outer layer does not necessarily have a heat-enduring feature. Consumers may be attracted by the intermediate layer with decoration visible from outside. If the outer layer is made of transparent and heat-enduring plastic, its cost should be expensive, raising up the cost of the whole mug. Then consumers may buy mugs made of stainless steel instead of those made of plastic. Besides, if the outer layer 1 is made of opaque heat-enduring plastic, the mug may not be attractive to consumers because of impossibility to draw curiosity of consumers. Most conventional double layer mugs use transparent but not heat-enduring plastic, and when liquid of high temperature flows out to the outer layer 1, the edge of the outer layer 1 may release toxic gas to harm a use's health.